Do you think I would be able to connect to the digital voltmeter module signals and use them to store the voltage values into a buffer??
I mean to save me time from setting up the sampling circuit myself.
The voltmeter readings will be used by software to do calculations for circuit analysis. So I thought it would be convenient to get a voltmeter and interface its signals to my software rather than build a circuit to sample the values.
If you can make soldering on the LCD inputs of the multimeter then you can do it but I don't think its practical.
Also, there are some multimeters with PC interface (like this http://www.apogeekits.com/multimeter_dvm345di.htm) but I don't know how you can read the values from their software.
Use an analog to digital converter IC and take its digital output to drive a display (seven segment or LCD) to view the result (measured voltage). If you want you can send this digital signal to a PC for processing etc.